Hitherto, a developing device in an electro-photographic image forming apparatus includes a casing, a developing roller, and a blade. The casing accommodates developer. The developing roller carries the developer. The blade contacts the developing roller with the developer interposed therebetween and regulates the thickness of the developer layer carried by the developing roller. Further, the blade includes a rubber portion and a support plate. The rubber portion regulates the thickness of the developer layer carried by the developing roller. The support plate supports the rubber portion.
In the developing device, the developing roller carries the developer accommodated in the casing. The rubber portion has a contact region that forms a nip with respect to the developing roller, and regulates the thickness of the developer layer carried by the developing roller in the contact region. Further, the developing roller carries the developer of which the thickness is regulated to a developing region between a photosensitive drum and the developing roller, and supplies the developer to an electrostatic latent image formed on the surface of the photosensitive drum, so that a developer image is formed thereon (see Japanese Patent Application Publication No. H06-186838).